Swede Momsen: Diving & Rescue - Rescue Chamber
McCann Rescue Chamber (Milne Special Collections and Archives Department,
University of New Hampshire Library, Durham, NH)
Momsen, traumatized by the sinking of the S-51 and learning that
the men had survived the wreck only to be trapped inside the submarine
at the ocean's bottom, thought of a way to rescue trapped Submariners.
He would build a large steel bell-shaped chamber, which could be
lowered with cables down to the escape hatch on a sunken submarine.
A watertight seal to the submarine could be achieved by placing
a rubber gasket around the diving bell's bottom and reducing the
air pressure once the bell was over the escape hatch. Then, the
hatch could be opened, and the trapped Submariners could climb aboard.
A hatch on the top of the bell would allow the rescued Submariners
and diving bell operators an easy way out of the bell.
The diving bell went through a series of tests off the shores of
Key West, Florida. Based on these tests, Momsen had several changes
in mind for the bell, but was sent to the Bureau of Construction
and Repair to teach Submariners how to use the Momsen Lung before
he could make the changes. Lieutenant Commander Allan McCann was
put in charge of the revisions on the diving bell. When the bell
was completed in late 1930, it was introduced as the McCann Rescue